This paper is concerned with identifying changes in the time series of water and sediment discharge of the Luoyugou, which is a semi-arid agricultural basin of the Loess Plateau within northwest China. The gradual trend test (Mann-Kendall (M-K) test) was employed on annual water discharge and sediment load series (from 1986 to 2008) in Luoyugou. The M-K test indicates that water discharge in the Luoyugou basin shows a significant decreasing trend and an abrupt shift in 1994. Remote sensing and geographic information system(GIS) techniques were used to inventory temporal changes of land cover changes in the watershed. A significant increase in terraced areas and woodland areas, from 942 km2 and 697 km2 to 3.501 krr12 and l.629 km2, respectively, occurred between 1986 and 2004, while the slope-cultivated area decreased significantly over the years, which is a total reduction of 7g%. from 4.358 km2 to 895 km2. Hydrological connectivity was reduced and water-generation ability decreased as the terraced areas increased. Compared with the runoff and sediment discharge pre-1994. annual runoff and sediment discharge post-1994 were reduced by 63.5% and 46.3%. respectively. The results of this study could improve our understanding of the hydrological effects of land cover and climate change and highlight the importance of considering the effects that land cover changes have on water resources for an informed decision on proper catchment planning and management.
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